David Beckham has hired a private detective to hunt down prostitute Irma Nici and serve her with a personal £5million writ for damages.

The high-class hooker has been secretly tailed for three days in New York as Becks’ powerful legal team prepare the papers to sue her.

They have found her hiding out in the city’s luxury W Hotel... STILL touting for hundreds of thousands of pounds the vile and sordid ­allegations that he paid for sex with her and another vice girl.

But 26-year-old Nici’s story was dramatically falling apart last night as the Sunday Mirror reveals that she has no proof to back her lurid claims.

Father-of-three Becks, 35, and wife Victoria, 36, were so incensed by Nici’s wild stories of three-in-a-bed sex that he ordered the detective to track her down and watch her every move.

As well as getting ready to personally serve a writ on Nici within the next 24 hours, ­Beckham’s lawyers filed a suit against the US magazine she sold her story to, In Touch, for “slander and ­intentional infliction of emotional ­distress”, as well as suits in ­Germany – where publisher Bauer’s parent corporation is based and where the story has also been published.

It came as Nici vainly tried to sell her story to the British Press – but without a shred of proof to back it up.

The Sunday Mirror can reveal she is desperate for cash after leaving her UK home this year with a string of debts and facing court action over unpaid bills.

Now, to prove their marriage is ­stronger than ever, David is set to whisk Victoria away for a­ ­romantic break for “peace and solitude” in the beautiful Californian hills around Napa Valley, where they have a secret holiday home.

The couple will head to the area – an hour’s flight from their Los Angeles home – after David ­returns from Trinidad, where this weekend he is publicly supporting England’s 2018 World Cup bid.

A source close to the couple said: “Victoria has stood by David ­because they both know the ­rumours are untrue.

“He has told her he will take her to Napa ­Valley this weekend. He is impressed by how calm and strong she has been ­throughout this. He’s taking her away to a luxury timeshare-style property they have bought, to say thanks for ­being so supportive and to show her how much he loves her.”

Bosnian-born Nici claims she was paid to have sex with David twice in 2007 – once in a threesome with another girl in a New York hotel and again for sex at Claridge’s Hotel in London.

Beckham immediately issued a denial when the story was ­published in the US magazine.

As well as his British legal team Harbottle and Lewis, headed by the Queen’s solicitor Gerrard ­Tyrrell, Becks has also hired US trial lawyer Bert Deixler.

He also wants to sue notorious madam Kristin Davis, who went on the record to back up Nici’s claims, and is said to be complicit in the fabrication of the story. Davis was recently jailed for four months for providing ­prostitutes for disgraced former New York governor Eliot Spitzer.

If successful, the England and LA Galaxy star could land an historic payout of an estimated £20million, legal experts have estimated.

Brunette Nici fled to America in May owing thousands of pounds at the £700,000 two-bedroom flat in west London where she worked as a hooker for a year.

Neighbours say they had ­complained constantly about her ­clients, who would turn up at all hours.

Banker Tim Lan, 28, who lived next door, said: “I go to work early and come back late and there were always men in the corridor outside her flat, spitting on the carpet or banging on the door to get in. It was obvious what was going on. They were there at six in the morning and last thing at night, different men all the time.

“The walls are thin and I could hear what was going on, or if she was arguing with one of them over money. I never got any sleep.

“I tried knocking on her door to complain but even though she was in there she never came out. The only time I heard her outside was when she came into the corridor to pepper-spray one of her ­customers who was kicking off.”

He added: “I spoke to one of the security guards and they knew what was going on too. We were all relieved when she did a flit, but since then there’s been people round trying to find her as she owes them money.”

John Laurie, 42, who moved in to Nici’s former flat last month, said: “There’s debts to the council, the landlord in Hong Kong, the TV licence people, credit card ­companies, everything.

“There’s always people buzzing the intercom looking for her. I’ve given up even looking at the bills for her, because there are so many. I just tear them up and throw them in the bin.